Nebraska executed Carey Dean Moore on Tuesday morning in the state’s first death by lethal injection.

Moore, 60, had served 38 years on death row for shooting and killing cab drivers Reuel Van Ness and Maynard Helgeland in the summer of 1979, according to the Omaha World-Herald. He had said he was ready to die.

“We could see him mouthing some words toward his witnesses, it was clear he said I love you several times,” witness Brent Martin of Nebraska Radio Network said at a news conference after the death, KLKN-TV in Lincoln, Nebraska, reports.

The fatal drug cocktail used for Moore’s execution had never been used to put a person to death, the Lincoln Journal Star reports. The concoction included sedative diazepam, muscle relaxant cisatracurium, potassium chloride and fentanyl.

The drug mixture is controversial, because if the substances did not work as planned, Moore could have suffered extreme pain. Friday, a lawyer for the drug company behind the paralyzing drug said it might not be effective if it wasn’t stored at the proper temperature, the World-Herald reports.

Witnesses reported no complications, only some coughing before Moore stopped moving. Moore died at 10:47 a.m. CT surrounded by three people, a clergy member and four media member witnesses, according to KLKN.

Moore released a “last statement,” where he apologized to his brother, Donald, who was with him during his first murder.

Monday, the American Civil Liberties Union of Nebraska filed a motion to delay Moore’s execution on behalf of eight death row inmates, KETV-TV, in Omaha, Nebraska, reports. After the execution, ACLU of Nebraska Executive Director Danielle Conrad condemned the decision.

“This execution of Carey Dean Moore does not comport with Nebraska’s proud tradition of open government,” Conrad said in a statement Tuesday. “Today stands as the most recent dark chapter in Nebraska’s troubled history with the death penalty.”

In 2016, Nebraska reinstated the death penalty. Before Moore, the state had executed 37 people, the last being killed by an electric chair.